Oh yeah,
I read the instructions and found this:
"For Arduino use, pins 1~4 are the minimum necessary to use one module."
and
"x is the Arduino digital pin connected to the module cable pin 4, y is the Arduino digital pin connected to the module cable pin 3, and z is the strobe pin. So if you had one module with data, clock and strobe connected to pins 8, 7, and 6 you would use: TM1638 module(8, 7, 6);"
If I got this right then I will connect
display Vcc (5V) -> Arduino 5V
display GND -> Arduino GND
display CLK -> Arduino digital pin 8
display DIO -> Arduino digital pin 7
display STB1 -> Arduino digital pin 6
Did I get it? Any comments? All ideas welcome! 